... would have V-ed ...

　　結構︰主詞＋would have＋過去分詞

　　說明︰此句型意為原本會但卻未如此。用以表示與過去事實相反的假設語氣。

　　He would have attended meeting, but upon learning that he had no time, he dropped the idea.

　　他原本要出席會議的，但知道沒有時間，就打消了這個念頭。

　　I would have told you the truth, but you didnt give me a chance.

　　我本來要告訴你事情的真相，但是你不給我機會。

　　I would have done it, but I had no time. 我本來要辦這事的，可是沒時間。

　　She would have married him, but when she learned that he was a rascal, she parted with him.

　　她本來會嫁給他的，但知道他是個流氓后，她就離開他了。

　　... could have V-ed ...

　　結構︰主詞＋could have＋過去分詞

　　說明︰此句型意為原本能夠但卻未如此。

　　He could have bought the car, but soon his company went bankrupt.

　　他本來能買那輛車的，但沒多久他的公司就倒閉了。

　　He could have finished it on schedule, but somehow he fell behind.

　　他原本能按預定進度做完這件事的，但不知怎地卻落后了。

　　I could have done it if I had wanted to. 如果我那時想做，我能做得到的。

　　... should have V-ed ...

　　結構︰主詞＋should／ought to have＋過去分詞

　　說明︰此句型意為原本應當但卻未如此。此句型表示沒有實現之過去的行為、狀態，含有講話者的責難或遺憾之意。

　　You should have spoken up in the meeting. 會談時你實在應該發言（然而你卻沒有）。

　　He should at least have come to say good-by. 他至少也該來道個別（然而卻沒來）。

　　He ought to have kept his promise. 他原本應該遵守自己的諾言。

　　You should have been more careful in money matters. 在錢方面，你本當更小心點的。

　　He ought to have arrived there by now. 他現在應該已經到那里了。

　　The drama drew a capacity audience; you should have gone to see it.

　　這出戲吸引了滿場觀眾；你真該去看的。

　　I should have known better

　　結構︰主詞＋should have known better（than to＋原形動詞）

　　說明︰此句型意為本來不應該那樣笨（而），是指已經做過之事，而 know better（不致那樣笨）是指未做之事。

　　I should have known better. 我本來不應該那樣笨。

　　You should have known better than to talk like that. 你本應更懂事而不致說這樣的話。

　　You should have known better than to go mountain climbing alone.

　　你本來不該笨得單獨去爬山。

　　I know better than to go swimming after dinner. 我不致笨得吃過飯就去游泳。

　　... would have V-ed ...

　　結構︰主詞＋would have＋過去分詞

　　說明︰此句型意為原本會但卻未如此。用以表示與過去事實相反的假設語氣。

　　He would have attended meeting, but upon learning that he had no time, he dropped the idea.

　　他原本要出席會議的，但知道沒有時間，就打消了這個念頭。

　　I would have told you the truth, but you didnt give me a chance.

　　我本來要告訴你事情的真相，但是你不給我機會。

　　I would have done it, but I had no time. 我本來要辦這事的，可是沒時間。

　　She would have married him, but when she learned that he was a rascal, she parted with him.

　　她本來會嫁給他的，但知道他是個流氓后，她就離開他了。

　　... could have V-ed ...

　　結構︰主詞＋could have＋過去分詞

　　說明︰此句型意為原本能夠但卻未如此。

　　He could have bought the car, but soon his company went bankrupt.

　　他本來能買那輛車的，但沒多久他的公司就倒閉了。

　　He could have finished it on schedule, but somehow he fell behind.

　　他原本能按預定進度做完這件事的，但不知怎地卻落后了。

　　I could have done it if I had wanted to. 如果我那時想做，我能做得到的。

　　... should have V-ed ...

　　結構︰主詞＋should／ought to have＋過去分詞

　　說明︰此句型意為原本應當但卻未如此。此句型表示沒有實現之過去的行為、狀態，含有講話者的責難或遺憾之意。

　　You should have spoken up in the meeting. 會談時你實在應該發言（然而你卻沒有）。

　　He should at least have come to say good-by. 他至少也該來道個別（然而卻沒來）。

　　He ought to have kept his promise. 他原本應該遵守自己的諾言。

　　You should have been more careful in money matters. 在錢方面，你本當更小心點的。

　　He ought to have arrived there by now. 他現在應該已經到那里了。

　　The drama drew a capacity audience; you should have gone to see it.

　　這出戲吸引了滿場觀眾；你真該去看的。

　　I should have known better

　　結構︰主詞＋should have known better（than to＋原形動詞）

　　說明︰此句型意為本來不應該那樣笨（而），是指已經做過之事，而 know better（不致那樣笨）是指未做之事。

　　I should have known better. 我本來不應該那樣笨。

　　You should have known better than to talk like that. 你本應更懂事而不致說這樣的話。

　　You should have known better than to go mountain climbing alone.

　　你本來不該笨得單獨去爬山。

　　I know better than to go swimming after dinner. 我不致笨得吃過飯就去游泳。